The ongoing drought in the western United States has garnered a lot of public attention in recent months, with national news media focusing on California and the state’s policy responses to manage a dire water situation that has and will continue to affect millions of people and billions of dollars of economic activity. Three questions repeatedly come up around the situation: (1) is the drought caused by climate change?; (2) why are some water users facing severe restrictions while others are not?; and (3) under what authority is the state imposing restrictions?
Answers to these questions are complex, of course, and I can’t do them justice here in a brief post. But suffice to say that the legal institutions under which we have developed and allocated water in the west—and in California in particular—will play a major role in responding to the triple social, economic, and ecological crises caused by the continuing drought. As for the first question, scientists are unable to determine with confidence that the drought has been caused by climate change—but it is clear that increasing frequency, duration, and intensity of drought is likely with climate change. Moreover, the combination of drought (which is technically a measure of the amount of precipitation an area has received) and increased heat in the atmosphere (which may occur with our without drought) is likely to increase with climate change. Scientists estimate that only one-quarter of historic years were both dry and hot—which is when both people and ecosystems demand more water but have a harder time getting it. Future climate conditions are likely to increase the likelihood of that combination, however, to about half of the time. That is an enormous increase in the likelihood of current conditions becoming “normal.”
Abnormal is the new normal. So our response to the ongoing drought—which has been coupled with much higher temperatures than historic averages (there has never been a “normal” condition of either precipitation or temperatures here)—will be a test run for how we manage climate change over the coming century or more.
That test run is stressing our legal institutions for allocating water in the west, which were developed in a more technologically optimistic age that was also both wetter and cooler than our likely future climate and much less concerned about the environmental impacts of our water development. Nevertheless, California water law and the allocation of water rights operate with two important background principles that limit whether a water rights holder can fully exercise that water right: (1) the need to make “reasonable” use of water for a “beneficial” use and (2) the need to protect public trust resources when doing so. Having a water right (“paper water”) isn’t the same as being able to divert water and use it (“wet water”).
The reasonable and beneficial use doctrine is clearly embodied in the California Constitution under Article X, section 2. It was last seriously tested in the 1967 case of Joslin v. Marin Municipal Water District, where the court held that the standard of “reasonable” use can evolve with changing circumstances. The Marks v. Whitney court then held in 1971 that the scope of California’s public trust doctrine also evolves with changing social conditions, and that principle was applied in 1983 in the National Audubon case that required the State Water Resources Control Board to reconsider water rights it had granted to the City of Los Angeles in 1941. The Board ultimately modified those water rights to protect Mono Lake in 1994.
Those three cases—Joslin in 1967, Marks v. Whitney in 1971, and National Audubon in 1983—clearly established boundaries on the private exercise of long-held water rights in light of changing conditions. Subsequent court cases have deepened the foundation for the state’s authority to modify water rights to protect the public trust. The ongoing drought may represent such a changing condition, so the Board may have authority to curtail even long-held “senior” water rights holders with either riparian or pre-1914 water rights. The prospect of such a move—which would raise deeper questions about whether their water use is “reasonable” or not—led many agricultural users to agree to “voluntary” reductions of 25% last week (which happen to match what urban users are facing). Those “voluntary” reductions and mandatory restrictions will help us get through the year, but they won’t be sufficient to address the reality of the new “normal” being a hotter, drier, less predictable climate pattern and a more urban population with environmental values. Ultimately, the legislature and the water board and the courts will need to closely reexamine the reasonable use doctrine in light of the new climate regime. When that happens, many long-term water rights holders will feel threatened and try to fight any reallocations.
But restructuring the allocation of water rights—both among beneficial uses (e.g., from agriculture to urban) and to protect public trust values (e.g., to leave more water in the stream) need not be resolved through winner-take-all legal battles. Instead, urban water users have a strong interest in making investments to help agricultural water users maintain economically viable production through more efficient use of water. In some cases, this will allow transfers to urban uses or more instream flows; in other cases, though, the loss of return flows from agricultural will diminish downstream availability. Therefore, opportunities for win-win solutions will vary as a function of local hydrology, plumbing, economics, and the specific structure of water rights among the parties. At this point, we should be looking for these opportunities rather than casting blame on one water user or another. We can manage our water allocation more efficiently without either displacing agriculture in the state or banning particular crop exports or destroying California’s aquatic environment. The key is to recognize how the law can adapt to face this challenge.